Agreed, training matters, but I believe honesty is key here, as I said earlier, DDG, even though he is probably the highest paid GK in Europe, DDG is not as good as Allison, Ederson or Neuer, so Henderson wanted to compete here, but was never given any chances to do so, if the managers (Ole & Ralf) thought he was not good enough to even compete, then I think that should have been communicated to him clearly and he should have been told that he is here as a backup, Romero for example accepted the backup role when he joined us, but Henderson made it clear he always wanted to be No.1, and Ole promised him that too, so he is at least owed a chance to compete and not be totally ignored.
I must reiterate that my argument is about the club's handling of Henderson, I still think Henderson is stupid to say what he said publicly.